phenomenon
A fact or event that can be observed and studied.
ExampleThe lecture describes the phenomenon before explaining its possible causes.
ExampleThe passage presents several theories about this natural phenomenon.
Usage Scenarios
Science lecture
Recognize phenomenon when the professor introduces an observed event before explaining causes or examples.
ExampleThe professor explains the phenomenon of birds changing migration routes.
Reading passage structure
Recognize it when the passage first describes something and then presents causes.
ExampleThe passage identifies the phenomenon before comparing two explanations.
Usage Guide
Recognize phenomenon when a passage or lecture discusses an observable event, pattern, or situation. TOEFL science lectures often introduce a phenomenon and then explain causes.
High-value patterns include explain a phenomenon, observe a phenomenon, natural phenomenon, and social phenomenon. These combinations fit academic reading and listening.
Be careful with the plural. One is a phenomenon; more than one are phenomena. TOEFL passages may use both.
Word Forms & Word Building
Phenomenon comes from roots connected with appearing or being observed; TOEFL uses it for something researchers can notice and explain.
Phenomena is the plural form, preserved from Greek. Use it when discussing several observable events or patterns.
Phenomenal is formed with the adjective suffix -al but has a different common meaning: extremely good or impressive, not the main TOEFL academic sense.
Meaning Boundaries
Phenomenon vs event
Event can be a single happening. Phenomenon is often broader and studied because it needs explanation.
Phenomenon vs theory
A phenomenon is what is observed, such as migration or erosion. A theory explains why that observed pattern happens.
Register
Phenomenon is academic and common in TOEFL biology, psychology, geology, astronomy, and sociology topics.
Memory Tricks
Think observed thing. If researchers can notice and study it, phenomenon may fit.
Remember the plural pair: phenomenon -> phenomena, because TOEFL passages may switch from one observed process to several related patterns.
In notes, write P next to the thing being explained, then add causes or theories below it.
Common Traps
Do not use phenomena as singular in formal TOEFL writing.
Do not confuse phenomenon with phenomenal. Phenomenal is usually evaluative; phenomenon is analytical.
When a passage asks for cause, separate the phenomenon from the explanation.